DIMERS ON SQUARE LATHCES: ORIENTATION DEPENDENT ACTIVITIES.

Past studies of a mixture of non-overlapping rigid polymers distributed on square lattices were limited to polymers having the
same activity regardless of orientation. Here, we address the problem of a single species, dimers, possessing different activities
depending on their orientation, in the absence of both dimer—dimer and dimer—lattice interaction energies. The lattices considered
consist of two, three, four and five infinite strips of equally spaced lattice sites (M=2, 3,4, and 5). We propose an improved
approximation technique for the study of the statistics of this system of dimers distributed on the infinite two-dimensional lattice
(M=infinity).